Democratic Party of Japan chief Katsuya Okada announced Tuesday that he will run in the party's presidential race on Sept. 13, with a majority of party members backing his bid for re-election.

Okada, who led the DPJ to huge gains in the House of Councilors election last month, is likely to be uncontested in his bid for a two-year term. His current term expires at the end of September.

"I became the party leader (three months ago) not because I wanted to," Okada told reporters, referring to his appointment after Naoto Kan stepped down over his past failure to pay into the mandatory national pension system.